Nuclear fusion is expected to become a future energy source as an alternative to fossil fuel, etc. In particular, in the field of laser fusion that is a system of inertial confinement fusion, since a fast ignition system using peta watt (PW) laser light with ultrahigh power was proposed in the early 1990s, it has been energetically developed by various research institutes, and the fundamental study thereof is being rapidly developed.
In laser fusion using direct irradiation represented by a fast ignition system and a central ignition system, by irradiating laser light onto a nuclear fusion target (pellet), fuel is compressed (imploded) to the central portion of the target, and an ultrahigh-density state is created. At this time, for stably causing inertial confinement fusion, high-density compression of fuel is essential, and for this, the nuclear fusion target must be irradiated and compressed as uniformly as possible. For example, a conventional configuration for obtaining uniform irradiation of laser light, a nuclear fusion device in which irradiation coordinates of 60 laser lights are set to be spherically symmetrical is known (refer to Non-Patent Literature 1 listed below).